In an IEEE 802.11 compliant communications system (also known as WiFi), an access point (AP) serves one or more stations (STA) by receiving transmissions from the one or more STA and forwarding the transmissions to their intended destinations. Similarly, the AP receives a transmission intended for one of its STA and forwards the transmission to the STA. A transmission occurs over unidirectional channels referred to as communications links. A transmission from a STA to the AP may be referred as an uplink (UL) transmission, while a transmission from the AP to a STA may be referred to as a downlink (DL) transmission.